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Evans, CEL orcid.org/0000-0002-4065-4397, Christian, MS, Cleghorn, CL et al. (2 more authors) (2012) Systematic review and meta-analysis of school-based interventions to improve daily fruit and vegetable intake in children aged 5 to 12 y. The American Journal of Clinical Nutrition, 96 (4). pp. 889-901. ISSN 0002-9165
https://doi.org/10.3945/ajcn.111.030270
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Systematic review and meta-analysis of school-based
interventions to improve daily fruit and vegetable
intake in children aged 5 to 12 years
Keywords: fruit, vegetables, RCT, meta-analysis, schools, children
Word count: 4610
Running title: Review of school based interventions
No specific funding was obtained for this review
Charlotte E.L Evans, (Lecturer in nutritional epidemiology) Nutritional Epidemiology
Group, School of Food Science and Nutrition, University of Leeds, LS2 9LN
Corresponding address as above
Email address: c.e.l.evans@leeds.ac.uk
Telephone: 0113 343 35596 Fax: 0113 343 2982
Meaghan S. Christian, (PhD student) Nutritional Epidemiology Group, School of Food
Science and Nutrition, University of Leeds, LS2 9LN
Christine L. Cleghorn, (Research Fellow) Nutritional Epidemiology Group, School of
Food Science and Nutrition, University of Leeds, LS2 9LN
Darren C. Greenwood, (Senior Lecturer) Biostatistics Unit, Centre for Epidemiology
and Biostatistics, University of Leeds, LS2 9LN
Janet E. Cade (Head of Group) Nutritional Epidemiology Group, School of Food
List of authors last names for the purpose of PubMed indexing (in alphabetical order)
Cade Christian Cleghorn Evans Greenwood
Abbreviations
Abstract
1Background: No reviews to date have assessed the impact of a range of multi- and single-
2
component school based programs on daily fruit and vegetable intake using meta-analysis. 3
Objectives: The aim was to quantify the impact of school-based interventions on fruit and
4
vegetable intake in children aged 5 to 12 years. 5
Design: A systematic literature review was carried out to identify randomized and
non-6
randomized controlled trials based in primary schools and designed to increase portions of 7
daily fruit and/or vegetable intake. Medline, Cochrane libraries, Embase, PsychInfo and 8
Educational Information Centre were searched from 1985 to 2009. Data was extracted and 9
mean effect sizes were calculated using random effects models. 10
Results: A total of 27 school-based programs involving 26,361 children were identified that
11
met the inclusion criteria and assessed daily weight of fruit and vegetable intake combined, 12
fruit intake only or vegetable intake only; and 21 were used in meta-analyses. The results of 13
the meta-analyses indicated an improvement of 0.25 (95% CI 0.06, 0.43) portions of fruit and 14
vegetable daily intake if fruit juice was excluded and an improvement of 0.32 (95% CI 0.14, 15
0.50) portions if fruit juice was included. Improvement was mainly due to increases in fruit 16
consumption, not vegetables. The results of the meta-analyses for fruit (excluding juice) and 17
vegetables separately indicated an improvement of 0.24 (95% CI 0.05, 0.43) portions and 18
0.07 (95% CI -0.03, 0.16) portions respectively. 19
Conclusions: School-based interventions moderately improve fruit intake, but have minimal
20
impact on vegetable intake. Further studies are needed to address the barriers for success in 21
changing dietary behaviour, particularly in relation to vegetables. 22
Introduction
24The long-term health benefits of a diet high in fruit and vegetables in adulthood are well 25
documented. High intakes of fruit and vegetables are associated with a reduced risk of all 26
cause mortality (1) many cancers, (2-4) CVD (5-6) and determinants of CVD (7-11) major 27
causes of death in developed countries. (12) High fruit and vegetable intakes may also be a 28
risk factor for obesity (13) although this is disputed. (14-15) High fruit and vegetable intake 29
is associated with a better quality diet lower in energy dense foods and higher in fibre. (16-30
18) and findings from the global Burden of Disease 2000 study suggest that 4.4% of the 31
overall burden of disease in Europe is attributable to low intakes of fruit and vegetables. (19) 32
Childhood levels of fruit and vegetables may be related to intakes in later life (20) resulting in 33
close links between poor intakes in childhood and adulthood. Surveys of children’s fruit and 34
vegetable intake have reported low intakes of fruit and vegetables in most American, 35
European and Australian children of between 2 to 3 portions per day, (16, 21-28) well below 36
the 5 portions (400g) recommended by many government departments of health. (29-30) 37
A range of potentially modifiable characteristics are reported to be associated with higher 38
intakes of fruit and vegetables in children. These include good availability and accessibility, 39
(31-38) taste preference and lack of neophobia, (34, 37, 39) better home support (40) 40
knowledge of the national recommendations, (31, 41-42) interested in a healthy diet, (42-44) 41
and verbal praise. (38, 45) These factors provide a wealth of information to shape the design 42
of school and community based interventions to increase fruit and vegetable intake in 43
children and have been incorporated into intervention programs. (46) Single component 44
programs provide free or subsidized fruit to children to increase availability while multi-45
component programs provide a range of components such as nutrition education in the 46
curriculum, improvement of the school environment to enable healthy choices, and 47
communication with parents to increase family support. 48
A number of reviews of school programs to improve fruit and vegetable consumption have 49
been conducted, (47-51) two of which have included a meta-analysis enabling the impact of 50
programs to be quantified. Of the two reviews which included meta-analysis, one included a 51
small number of studies (51) and one pooled studies where fruit and vegetable intake was 52
assessed either over the school day or over the whole day, resulting in a high level of 53
programs as it did not take into account the fact that children may potentially increase their 55
consumption of fruit and vegetables while at school and compensate with reductions in home 56
consumption. (52) This high quality review is the first to provide a meta-analysis of a wide 57
range of multi-component and single component studies which measured the impact of 58
school based programs on daily fruit and vegetable consumption. Advanced analysis 59
techniques were used and the impact of programs was reported in terms of numbers of 60
portions of fruit and vegetables. Important sources of heterogeneity were taken into account 61
for the first time by presenting the results from studies which measured fruit and vegetables 62
but not fruit juice. This is important as reviews of the health benefits of fruit and vegetables 63
generally exclude juice which may have different associations with health outcomes. Results 64
of the impact on fruit and vegetables separately are reported for the first time in meta-65
analyses. 66
Improvements in daily fruit and vegetable consumption have the potential to achieve 67
significant public health benefits and this review identifies school-based trials targeting fruit 68
and vegetable intake in children aged 5 to 12 years to assess the impact of these programs. 69
Methods
70Search strategy
71
An unpublished protocol was designed and agreed by all authors at the start of the review. 72
The following bibliographic databases were searched: the Cochrane Central Register of 73
Controlled Trials, OVID MEDLINE (1986 to 2009), Global Health (1973 to 2009), 74
PsychInfo (1987 to 2009), Educational Resources Information Centre (1985 to 2009), 75
EMBASE and CINAHL. The search strategy method for MEDLINE included research terms 76
in the following areas: child, fruit, vegetable, specific fruits and vegetables, public health, 77
health behavior, health promotion, health education, intervention studies and diet. This was 78
adapted so it could be used for the other databases, using keywords when MeSH terms were 79
not available. Reference lists were searched for additional citations. 80
Inclusion and exclusion criteria
81
Dietary intervention studies in a school setting involving children aged between 5 and 12 82
years (at the start of the intervention) were included. Trials (with or without randomization) 83
standard assessment measures such as food diaries using weighed/non-weighed methods, 24 85
hour diet recall, or food frequency questionnaires. 86
Studies were excluded if the intervention focused on eating disorders, such as anorexia 87
nervosa or bulimia, or if data on children of this age group could not be extracted separately 88
from other age groups. Trials involving fewer than ten participants were also excluded as 89
were those that included only obese children. 90
Trials were excluded if fruit and vegetable intake was measured solely on daily frequency of 91
consumption of fruit and vegetables rather than amount or portions consumed using a 92
standard portion size, as the weight of a piece of fruit or vegetable can vary. Studies were 93
excluded if they did not include a measure of variation such as standard deviation or standard 94
error. Studies were excluded if they did not report total daily fruit and vegetable 95
consumption, for example if they reported consumption at school only. Studies that only had 96
more than 2 years follow up were excluded as bias was likely to be considerable with loss to 97
follow up. 98
Definitions of exposure and outcome
99
The main outcome was the difference in portions (total weight in grams/80g) of fruit and 100
vegetables, separately and combined, consumed daily, excluding potatoes between the 101
intervention and control group. This is the agreed portion size for fruit and vegetables and no 102
government has set a smaller standard portion size for children. 103
The benefits of fruit juice consumption are not as clear as the benefits of fruit and vegetable 104
intake. Therefore, trials that included fruit juice together with fruit and vegetables were 105
analysed separately. Alternative wording from portion such as serving or serve were checked 106
to ensure that this was equal to 80g. If the portion or serving was different from 80g this was 107
recalculated. The US serving of half a cup of vegetables or medium size piece of fruit were 108
taken to be equal to a portion of 80g. 109
Selection of the studies
110
Two independent reviewers were involved in the study identification and data extraction. In 111
the first round of initial screening, the title and abstract of each article was checked for 112
eligibility by one of the two reviewers. Articles were excluded from the title and abstract if 113
they clearly did not meet inclusion and exclusion criteria as judged by the reviewer. In the 114
article was assessed for eligibility by both reviewers. Any disagreement between the two 116
reviewers on whether the article was eligible was resolved by discussion between the 117
reviewers, where necessary in consultation with a third reviewer. 118
Data extraction
119
Data was extracted by two independent members of the team (but not in duplicate). All the 120
data extracted was checked by a third member of the team trained and experienced in data 121
extraction. Data was extracted on data collection methods, length of program, drop-outs and 122
analysis methods. All studies were summarized according to the following aspects: type of 123
intervention, selection of population, outcomes, baseline and follow-up measures and 124
statistical analysis. Data on sample size, sample age, date and location of the study, type of 125
control group and unit of randomization were also extracted. 126
Wherever results for more than one follow-up period were reported, the longest follow up 127
period was used in the meta-analysis. The different types of activities included in the 128
intervention program were identified for each study. These included the following pre-129
specified elements: school lessons as part of the school curriculum; communications (either 130
with parents through newsletters or with students and teachers at school); food provision such 131
as availability of fruit and vegetables at lunchtime or in tuck-shops; free fruit and/or 132
vegetable distribution, food marketing such as incentives to buy more fruit and vegetables at 133
lunchtime including point of purchase incentives; food preparation and/or tasting during 134
school; home based projects including home-work carried out with the help of parents; 135
general improvements in the school environment (used if specific school based elements were 136
not described); community and industry involvement such as supermarkets or industry 137
partners. The final element reported by mainly US studies was goal setting and problem 138
solving, which indicated an over-arching theory based study of planned behavior was used. 139
Quality assessment of studies
140
Assessment of the quality of the trials was based on three criteria; reporting of sequence 141
generation criteria, allocation concealment and blinding of participants, personnel or outcome 142
assessors. Trials were considered to be at high risk of bias if none of the criteria were met, at 143
medium risk of bias if 1 or 2 of the criteria were met or at low risk of bias if all three of the 144
Statistical analysis
146
Statistical analysis was carried out in Stata version 10. Random effects models were used for 147
all meta-analyses to determine pooled estimates of differences in portions of fruit and 148
vegetables consumed in the intervention groups compared to control groups. If results were 149
reported as change from baseline to follow up in each group difference between groups was 150
calculated using the t-test. Heterogeneity was assessed using the I2 statistic, which describes 151
the proportion of total variation attributable to between-study heterogeneity. (53) I2 values of 152
less than 30% were considered to be low, values between 30-50% low to moderate, values 153
between 50-75% moderate to high and values above 75% high. I2 values of more than 50% 154
indicate that caution should be used when drawing conclusions from the data.(54) Forest 155
plots were examined to review heterogeneity between studies. Possible sources of 156
heterogeneity were explored, and included: trial design (randomized or not randomized), 157
geographical location, intervention type, diet assessment methodology, children’s age and 158
length of follow-up. Funnel plots were used to visually check for asymmetry and to 159
determine the possibility of publication bias. (53) 160
Results
161Literature search
162
The literature search outlined in the methods identified 2722 potential papers, including 316 163
duplicates (312 identified at the first stage and 4 identified at the screening stage): 592 papers 164
from Embase, 100 from Psychinfo and the remainder from Medline. A total of 67 papers 165
potentially meeting all the criteria as a result of screening titles and abstracts were identified. 166
2,656 papers were excluded (before de-duplication) based on the predetermined exclusion 167
factors. Many papers were excluded on medical grounds such as eating disorders (12 168
studies), nut allergy (396 studies) or other medical conditions that concerned negative aspects 169
of plants on health (711 studies). A number of papers were excluded where the outcome was 170
not daily weight of fruit and vegetables (439 studies) or were not controlled trials (1072 171
studies). Some studies were excluded due to the age of the children (25 studies). Scrutiny of 172
the remaining 67 papers identified 40 further papers for exclusion resulting in 27 studies 173
remaining. Reasons for exclusion at this second stage are provided in figure 1 with ‘wrong 174
age group and outcome other than daily weight of fruit and vegetables as the primary reasons 175
A summary of the studies included in the qualitative review on daily intake are displayed in 177
table 1. The sample size of each study represents the number of children included in the
178
analysis with baseline and follow up data available. The total number of participants 179
included in all studies was 26,361 with a mean of 909 children per study (median of 486). 180
Programs delivered a variety of interventions delivered over a range of 3 months for mainly 181
curriculum based programs to two academic years for many of the more complex programs. 182
The majority of the interventions consisted of more than one component and therefore were 183
categorized as multi-component programs. These interventions often comprised a home and 184
school element and tended to have a longer follow up time period than single component 185
programs. The single component programs were mainly free or subsidized fruit distribution 186
schemes. In most cases, control groups were either reported to receive an intervention at a 187
later date or usual care. Some studies did not report information on the control group and two 188
studies by Bere reported that the control group received a paid subscription for fruit 189
compared to the intervention group which received free fruit.(55-56) The unit of 190
randomization was normally the school but in two trials the unit of randomization was the 191
class(57-58) and in one study was the region.(59) The median difference in daily fruit and 192
vegetable intake between the control and intervention group for all studies included in the 193
qualitative review was 0.6 portions based on 27 studies with intervention groups having 194
higher intakes on average. 195
Six studies were excluded at the meta-analysis stage due to lack of measures of variation 196
(standard deviation, standard error or confidence interval) (57, 60-64) One study reported 197
total sample size but not sample size for each group. In this case the sample size was 198
estimated by assuming equal numbers of children in each group and the study included. (65) 199
One author replied to the request for further information on sample size for the control and 200
intervention group and was also included. (66) 201
All papers included reported fruit and vegetable intake over the whole day but some also 202
included fruit juice in the reported difference between groups.(65-68) Inclusion of fruit juice 203
was a strong determinant of heterogeneity and therefore the primary analysis (see figure 2) 204
included studies where only fruit and vegetables and not fruit juice were measured. Due to 205
the fact that this was not decided a priori a sensitivity analysis including all studies was 206
carried out in addition to the primary analysis (see figure 3). Three studies in the meta-207
analysis reported total consumption of fruit and vegetables and also fruit juice (65-66, 68) 208
meta-analyses are presented with differences in daily fruit only (figure 4) and vegetable 210
intake only (figure 5). 211
In the primary meta-analysis to determine differences in fruit and vegetable consumption 212
excluding fruit juice, the pooled estimate for interventions reported a daily difference of 0.25 213
portions (95% CI 0.06, 0.43 portions) with higher levels of fruit and vegetables in the 214
intervention group (figure 2). The difference between groups was significantly different from 215
zero (p<0.01). The I2 value was 49% (95% CI 0, 74%, p=0.04) indicating moderate levels of 216
heterogeneity. A funnel plot indicated that there was some suggestion of slight asymmetry 217
(plot supplied as supplementary data), but the Egger's test for asymmetry was not statistically 218
significant (p=0.58). In the sensitivity analysis to determine differences in fruit and vegetable 219
consumption including fruit juice, the pooled estimate for interventions reported a daily 220
difference of 0.32 portions (95% CI 0.14, 0.50 portions) with levels of fruit and vegetables 221
higher in the intervention group (figure 3). This difference was significantly different from 222
zero (p<0.01). Heterogeneity measured using I2 was moderate to high at 62% (95% CI 31, 223
79%, p<0.01). A funnel plot indicated that there was some suggestion of slight asymmetry 224
(plot supplied as supplementary data), but the Egger's test for asymmetry was not statistically 225
significant (p=0.21). 226
The meta-analysis of difference in fruit only, excluding fruit juice (figure 4) reported that 227
fruit was 0.24 (0.05, 0.43) portions higher in the intervention group. This difference was 228
significantly different from zero (p=0.01). However, heterogeneity was high with an I2 value
229
of 78% (95% CI 60, 87%, p<0.01). A funnel plot indicated that there was asymmetry (plot 230
supplied as supplementary data), and the Egger's test for asymmetry was statistically 231
significant (p=0.02). An analysis on all studies including those with fruit juice produced 232
similar results. The difference between groups was 0.28 (95% CI 0.12, 0.44) portions for all 233
studies which was significantly different from zero (p<0.01). Heterogeneity as denoted by I2 234
was high at 78% (95% CI 63, 86%, p<0.01) (forest plot not shown). Differences in vegetable 235
intake between control and intervention groups were much smaller (figure 5). A meta-236
analysis of vegetables only which included studies with fruit juice indicated an effect size of 237
0.07 (95% CI -0.03, 0.16) portions which was not significantly different from zero (p=0.16). 238
Heterogeneity was moderate to high with an I2 value of 72% (95% CI 54, 83%, p<0.01). A 239
funnel plot indicated that there was some suggestion of slight asymmetry (plot supplied as 240
supplementary data), but the Egger's test for asymmetry was not statistically significant 241
An investigation into potential sources of heterogeneity using meta-regression analysis found 243
no statistically significant associations between the estimates and whether schools were 244
randomized, not randomized or not made clear, trial design (multi-component or single-245
component), age of the children, type of dietary assessment or length of follow up (see Table 246
2). However there were non-statistically significant trends in the pooled estimates for trial 247
design. The pooled estimate for single-component studies was smaller, although 248
heterogeneity was higher than for all studies combined. Five studies reported results for two 249
follow-up periods. In three studies, Ransley,(52) Baranowski(66) and Reynolds,(65) the 250
interventions continued beyond the first follow-up data collection point. In two studies (56, 251
69) the final follow-up collection period was more than three months after the completion of 252
the intervention. Data reported at the latest follow up period was used for each study. 253
Quality of studies included in the meta-analyses
254
The quality of the 22 trials included in the meta-analyses was generally poor with evidence of 255
high risk of bias. One study reported on all three criteria and was therefore judged to be at 256
low risk of bias. (70) Ten studies reported on one or two criteria and were therefore judged 257
to be at medium risk of bias. (52, 58, 63, 66-67, 71-75) The remaining 11 trials were judged 258
to be at high risk of bias and did not clearly report sequence generation criteria, allocation 259
concealment or blinding of participants, personnel or outcome assessors. 260
Discussion
261Main findings
262
This review provides the first meta-analysis to quantify the impact of a range of school-based 263
interventions on daily consumption of fruit and vegetable intake in children aged 5 to 12 264
years. It is also the first review to quantify the differences in impact on vegetable compared 265
with fruit intake. School-based interventions of all types were estimated to improve daily 266
fruit and vegetable consumption by an average of a quarter to a third of a portion; equivalent 267
to 20-30g daily increase. Although most schemes aim to improve intake of both fruit and 268
vegetables most fail to increase vegetable intake by a useful amount with most of the 269
improvement in fruit intake. Studies that included fruit juice when assessing consumption of 270
fruit and vegetables tended to have higher intakes of fruit, juice and vegetables at baseline 271
strongly associated with health outcomes attenuated the impact of programs on daily fruit and 273
vegetable intake. 274
Comparison of different types of programs
275
School based interventions generally fall into two main categories, multi-component 276
programs that motivate and engage children and families to change their eating behavior and 277
single component programs that provide and distribute free or subsidized fruit and/or 278
vegetables. In this review, the multi-component programs tended to result in larger 279
improvements in fruit and vegetable intake but are diverse and can potentially be difficult to 280
replicate without considerable time, man-power and funds.(48) How well interventions are 281
implemented are reported to determine the impact of a program.(76-77) The single 282
component studies including free and subsidized fruit and vegetable distribution schemes 283
tended to be less effective although there were too few studies included to enable firm 284
conclusions to be made. Distribution schemes have recently been introduced in some schools 285
as part of national policies to increase children’s fruit and vegetable intake. These schemes 286
may offer little in terms of learned permanent improvement on children’s eating habits; 287
however fruit and vegetable intake may be moderately improved while receiving the fruit. 288
Teachers rating programs for ease of use, rate distribution programs easier to implement than 289
multi-component programs, (78) therefore long-term distribution programs may be a useful 290
option for governments. 291
Comparisons with previous reviews
292
Previous reviews based on qualitative analysis without meta-analysis report increases of 0 to 293
1 servings of fruit and vegetables per day. (49) (50) The results obtained here are similar to 294
those of a previous meta-analysis of seven studies, which reported an increase of 0.4 portions 295
of fruit and vegetables. This previous review included mainly multi-component studies and 296
did not exclude studies on the basis of including fruit juice which may explain the slightly 297
higher effect. (51) A recent review of programs to improve fruit and vegetable intake 298
stratified by type of intervention concluded that computer based interventions were the most 299
successful type of program and multi-component programs had no impact. This conclusion 300
was based on two analyses. Firstly a meta-analysis of only two programs using computer 301
games, one of which did not include fruit and vegetable intake over the whole day (only the 302
school day) and one of which included fruit juice. Secondly, the conclusions were based on 303
but due to high levels of heterogeneity as a result of including programs measuring only fruit 305
or vegetable intake and programs assessing fruit and vegetable intake over part of the day, it 306
was not possible to make firm conclusions.(47) In this review it was established that there 307
are currently not enough studies assessing daily intake of fruit and vegetables to determine 308
the impact of different types of studies although we identified a trend that multi-component 309
studies are more effective than single component-studies. 310
Strengths of this review
311
This review had a number of strengths. A range of single and multi-component programs 312
were included from different countries. Robust review methods were employed including the 313
use of a range of databases to find papers from a variety of sources and the use of two 314
reviewers to determine inclusions and exclusions. Furthermore, formal quantification of the 315
pooled estimates was carried out using meta-analysis. Studies were included that reported 316
frequency of consumption of fruit and vegetables as well as standard portion sizes or weight 317
in grams. 318
Measures were taken to reduce heterogeneity by restricting age group and only including 319
studies where standard methods of assessment were used. Fruit and vegetable intakes have 320
been shown to be underestimated by some methods (79) but no substantial differences by 321
assessment method were identified in this review. Studies that focused on obese children 322
were excluded as they may be expected to be more prepared to change their diet than children 323
in general. 324
Limitations of this review
325
The protocol was designed in 2008 using a Cochrane review protocol as a template and all 326
authors were involved in the design and agreement of the protocol. However, the protocol is 327
unpublished which is sub-optimal in meta-analysis. 328
Many studies published in this area are of poor quality design without a control group or with 329
poor randomization methods leading to biased reporting. Reporting of results was not 330
consistent and a number of studies did not report both fruit and vegetable consumption 331
combined. Successful programs may not have been included in the analysis due to a lack of 332
Future strategies
334
Some components from earlier multi-component programs have been incorporated into 335
national policy in some countries. For example, the curriculum in many countries includes 336
specific lessons on healthy eating.(80) In the UK children aged 4 to 7 years receive free fruit 337
and vegetables and receive a school meal meeting food based standards which include daily 338
fruit and vegetable provision, both of which are elements of recent multi-component 339
programs. However, there are some areas where very few, or no, trials have been reported in 340
this age group, such as studies where cooking or school gardening is the main component. 341
(81) Some types of studies such as tasting of fruit and vegetables were not included in the 342
review because of a lack of assessment of daily fruit and vegetable intake in these mainly 343
laboratory based studies; (82) however, exposing children who disliked vegetables for 14 344
days has been reported to increase liking and consumption of vegetables. (83) There is also 345
evidence that schools participating in gardening programs increase fruit and vegetable, 346
vitamin A, vitamin C and fibre intake. (84) Future RCTs in these areas may be expected to 347
further contribute to an increase in the intake of vegetables in particular which is badly 348
needed. There should also be a focus on families and home consumption of fruit and 349
vegetables. 350
Very few studies collected follow-up data a full year after the intervention, particularly if the 351
intervention was less than 6 months in duration. Those that did collect this type of data saw 352
moderate long-term impact on fruit and vegetable intake, (56) indicating that if intervention 353
programs are to have an impact on children’s health they must run continuously over long 354
periods of time and should not be considered as one-off solutions. Based on these results, 355
school based programs could be expected to increase fruit and vegetable intake by a quarter 356
to a third of a portion, but there is limited evidence of the impact on future health outcomes 357
from a daily increase of a third of a portion of fruit and vegetables at a population level. 358
In conclusion, school-based programs including distribution schemes have the potential to 359
moderately improve daily consumption of fruit. However these programs do not appear to be 360
successful at improving vegetable intake in school-children. More efforts are needed to 361
design programs to improve vegetable intake in children and to reduce barriers to positive 362
Acknowledgements
364CE put forward the initial idea to carry out the review, contributed to the searching, analysed 365
the data using meta-analysis, wrote the first draft and contributed to following drafts. MC 366
was involved in producing the original search criteria, the searching of papers and contributed 367
to all drafts. CC managed the search database, determined trial quality and contributed to all 368
drafts. DG provided essential statistical support for all analysis and contributed to all drafts. 369
JC provided essential support at all stages of the review and contributed to all drafts. We are 370
grateful to Camilla Nykjaer for checking the data. No conflict of interest was identified by 371
any of the authors. 372
373
References
3741. Bazzano LA, He J, Ogden LG, et al. Fruit and vegetable intake and risk of 375
cardiovascular disease in US adults: the first National Health and Nutrition 376
Examination Survey Epidemiologic Follow-up Study. Am J Clin Nutr 2002;76:93-9. 377
2. Boffetta P, Couto E, Wichmann J, et al. Fruit and vegetable intake and overall cancer 378
risk in the European Prospective Investigation into Cancer and Nutrition (EPIC). J 379
Natl Cancer Inst 2010;102:529-37. 380
3. Lunet N, Lacerda-Vieira A, Barros H. Fruit and Vegetables Consumption and Gastric 381
Cancer: A Systematic Review and Meta-Analysis of Cohort Studies. Nutrition and 382
Cancer 2005;53:1-10. 383
4. Steinmetz KA, Potter JD. Vegetables, fruit, and cancer prevention: a review. 384
J.Am.Diet.Assoc. 1996;96:1027-1039. 385
5. Dauchet L, Amouyel P, Hercberg S, Dallongeville J. Fruit and Vegetable 386
Consumption and Risk of Coronary Heart Disease: A Meta-Analysis of Cohort 387
Studies. The Journal of Nutrition 2006;136:2588-2593. 388
6. Ness AR, Powles JW. Fruit and vegetables, and cardiovascular disease: a review. Int J 389
Epidemiol 1997;26:1-13. 390
7. Bazzano LA, Li TY, Joshipura KJ, Hu FB. Intake of fruit, vegetables, and fruit juices 391
and risk of diabetes in women. Diabetes Care 2008;31:1311-7. 392
8. Harding AH, Wareham NJ, Bingham SA, et al. Plasma vitamin C level, fruit and 393
vegetable consumption, and the risk of new-onset type 2 diabetes mellitus: the 394
European prospective investigation of cancer--Norfolk prospective study. Arch Intern 395
Med 2008;168:1493-9. 396
9. Liu S, Serdula M, Janket SJ, et al. A prospective study of fruit and vegetable intake 397
and the risk of type 2 diabetes in women. Diabetes Care 2004;27:2993-6. 398
10. Appel LJ, Moore TJ, Obarzanek E, et al. A clinical trial of the effects of dietary 399
patterns on blood pressure. DASH Collaborative Research Group. N Engl J Med 400
1997;336:1117-24. 401
11. Miura K, Greenland P, Stamler J, Liu K, Daviglus ML, Nakagawa H. Relation of 402
vegetable, fruit, and meat intake to 7-year blood pressure change in middle-aged men: 403
12. WHO. Diet, Nutrition and the Prevention of Chronic Diseases. In: FAO, ed. Geneva, 405
2003. 406
13. He K, Hu FB, Colditz GA, Manson JE, Willett WC, Liu S. Changes in intake of fruits 407
and vegetables in relation to risk of obesity and weight gain among middle-aged 408
women. Int J Obes Relat Metab Disord 2004;28:1569-74. 409
14. Newby P. Plant foods and plant-based diets: protective against childhood obesity? 410
The American Journal of Clinical Nutrition 2009;89:1572S-1587S. 411
15. Ledoux TA, Hingle MD, Baranowski T. Relationship of fruit and vegetable intake 412
with adiposity: a systematic review. Obesity Reviews 2011;12:e143-e150. 413
16. Andersen LF, Overby N, Lillegaard IT. [Intake of fruit and vegetables among 414
Norwegian children and adolescents]. Tidsskr Nor Laegeforen 2004;124:1396-8. 415
17. McCrory MA, Fuss PJ, McCallum JE, et al. Dietary variety within food groups: 416
association with energy intake and body fatness in men and women. Am J Clin Nutr 417
1999;69:440-7. 418
18. Rolls BJ, Ello-Martin JA, Tohill BC. What can intervention studies tell us about the 419
relationship between fruit and vegetable consumption and weight management? Nutr 420
Rev 2004;62:1-17. 421
19. Pomerleau J, McKee M, Lobstein T, Knai C. The burden of disease attributable to 422
nutrition in Europe. Public Health Nutr 2003;6:453-461. 423
20. Maynard M, Gunnell D, Ness AR, Abraham L, Bates CJ, Blane D. What influences 424
diet in early old age? Prospective and cross-sectional analyses of the Boyd Orr cohort. 425
Eur J Public Health 2006;16:316-24. 426
21. Vereecken CA, De Henauw S, Maes L. Adolescents' food habits: results of the Health 427
Behaviour in School-aged Children survey. Br J Nutr 2005;94:423-31. 428
22. Rogers IS, Ness AR, Hebditch K, Jones LR, Emmett PM. Quality of food eaten in 429
English primary schools: school dinners vs packed lunches. Eur.J.Clin.Nutr. 430
2007;61:856-864. 431
23. Baxter IA, Schroder MJA. Vegetable consumption among Scottish children: a review 432
of the determinants and proposed strategies to overcome low consumption. British 433
Food Journal 1997;99:380. 434
24. Krebs-Smith SM, Cook A, Subar AF, Cleveland L, Friday J, Kahle LL. Fruit and 435
vegetable intakes of children and adolescents in the United States. 436
Arch.Pediatr.Adolesc.Med. 1996;150:81-86. 437
25. Timperio A, Ball K, Roberts R, Campbell K, Andrianopoulos N, Crawford D. 438
Children's fruit and vegetable intake: associations with the neighbourhood food 439
environment. Prev Med 2008;46:331-5. 440
26. Magarey A, Daniels LA, Smith A. Fruit and vegetable intakes of Australians aged 2-441
18 years: An evaluation of the 1995 National Nutrition Survey data. Australian and 442
New Zealand Journal of Public Health 2001;25:155. 443
27. Cockroft JE, Durkin M, Masding C, Cade JE. Fruit and vegetable intakes in a sample 444
of pre-school children participating in the 'Five for All' project in Bradford. Public 445
Health Nutr. 2005;8:861-869. 446
28. Gregory J, Lowe S, Bates CJ, et al. National Diet and Nutrition Survey (NDNS): 447
young people aged 4 to 18 years. London: the Stationery Office, 2000. 448
29. Munoz de CM, Chavez A. Diet that prevents cancer: recommendations from the 449
American Institute for Cancer Research. Int.J.Cancer Suppl 1998;11:85-89. 450
30. Department of Health. 5 A Day. 2005. 451
31. De Bourdeaudhuij I, te Velde S, Brug J, et al. Personal, social and environmental 452
predictors of daily fruit and vegetable intake in 11-year-old children in nine European 453
32. Hanson NI, Neumark-Sztainer D, Eisenberg ME, Story M, Wall M. Associations 455
between parental report of the home food environment and adolescent intakes of 456
fruits, vegetables and dairy foods. Public Health Nutr 2005;8:77-85. 457
33. Blanchette L, Brug J. Determinants of fruit and vegetable consumption among 6-12-458
year-old children and effective interventions to increase consumption. 459
J.Hum.Nutr.Diet. 2005;18:431-443. 460
34. Brug J, Tak NI, te Velde SJ, Bere E, de Bourdeaudhuij I. Taste preferences, liking and 461
other factors related to fruit and vegetable intakes among schoolchildren: results from 462
observational studies. Br J Nutr 2008;99 Suppl 1:S7-S14. 463
35. Gibson EL, Wardle J, Watts CJ. Fruit and vegetable consumption, nutritional 464
knowledge and beliefs in mothers and children. Appetite 1998;31:205-28. 465
36. Kratt P, Reynolds K, Shewchuk R. The role of availability as a moderator of family 466
fruit and vegetable consumption. Health Educ Behav 2000;27:471-82. 467
37. Neumark-Sztainer D, Wall M, Perry C, Story M. Correlates of fruit and vegetable 468
intake among adolescents. Findings from Project EAT. Prev.Med. 2003;37:198-208. 469
38. Weber Cullen K, Baranowski T, Rittenberry L, et al. Socioenvironmental influences 470
on children's fruit, juice and vegetable consumption as reported by parents: reliability 471
and validity of measures. Public Health Nutr 2000;3:345-56. 472
39. Galloway AT, Lee Y, Birch LL. Predictors and consequences of food neophobia and 473
pickiness in young girls. J Am Diet Assoc 2003;103:692-8. 474
40. Pearson N, Biddle SJ, Gorely T. Family correlates of fruit and vegetable consumption 475
in children and adolescents: a systematic review. Public Health Nutr 2009;12:267-83. 476
41. Kloek GC, van Lenthe FJ, van Nierop PW, Mackenbach JP. Stages of change for fruit 477
and vegetable consumption in deprived neighborhoods. Health Educ Behav 478
2004;31:223-41. 479
42. Johansson L, Thelle DS, Solvoll K, Bjorneboe GE, Drevon CA. Healthy dietary 480
habits in relation to social determinants and lifestyle factors. Br J Nutr 1999;81:211-481
20. 482
43. Thompson RL, Margetts BM, Speller VM, McVey D. The Health Education 483
Authority's health and lifestyle survey 1993: who are the low fruit and vegetable 484
consumers? J.Epidemiol.Community Health 1999;53:294-299. 485
44. Pollard J, Greenwood D, Kirk S, Cade J. Motivations for fruit and vegetable 486
consumption in the UK Women's Cohort Study. Public Health Nutr 2002;5:479-86. 487
45. Vereecken CA, Keukelier E, Maes L. Influence of mother's educational level on food 488
parenting practices and food habits of young children. Appetite 2004;43:93-103. 489
46. Baranowski T, Smith M, Hearn MD, et al. Patterns in children's fruit and vegetable 490
consumption by meal and day of the week. J.Am.Coll.Nutr. 1997;16:216-223. 491
47. Delgado-Noguera M, Tort S, Martinez-Zapata MJ, Bonfill X. Primary school 492
interventions to promote fruit and vegetable consumption: a systematic review and 493
meta-analysis. Prev Med 2011;53:3-9. 494
48. Van Cauwenberghe E, Maes L, Spittaels H, et al. Effectiveness of school-based 495
interventions in Europe to promote healthy nutrition in children and adolescents: 496
systematic review of published and 'grey' literature. Br J Nutr 2010;103:781-97. 497
49. Knai C, Pomerleau J, Lock K, McKee M. Getting children to eat more fruit and 498
vegetables: a systematic review. Prev.Med. 2006;42:85-95. 499
50. French SA, Stables G. Environmental interventions to promote vegetable and fruit 500
consumption among youth in school settings. Prev.Med. 2003;37:593-610. 501
51. Howerton MW, Bell BS, Dodd KW, Berrigan D, Stolzenberg-Solomon R, Nebeling 502
Vegetable Consumption: Meta and Pooling Analyses from 7 Studies. Journal of 504
Nutrition Education and Behavior 2007;39:186-196. 505
52. Ransley JK, Greenwood DC, Cade JE, et al. Does the school fruit and vegetable 506
scheme improve children's diet? A non-randomised controlled trial. 507
J.Epidemiol.Community Health 2007;61:699-703. 508
53. Egger M, Davey Smith G, Altman DG, eds. Systematic Reviews in Healthcare: Meta-509
analysis in context. 2nd ed: BMJ Books, 2008. 510
54. Higgins JPT, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-511
analyses. BMJ 2003;327:557-560. 512
55. Bere E, Veierod MB, Bjelland M, Klepp KI. Free school fruit--sustained effect 1 year 513
later. Health Educ Res 2006;21:268-75. 514
56. Bere E, Veierod MB, Bjelland M, Klepp KI. Outcome and process evaluation of a 515
Norwegian school-randomized fruit and vegetable intervention: Fruits and Vegetables 516
Make the Marks (FVMM). Health Educ Res 2006;21:258-67. 517
57. Hopper CA, Munoz KD, Gruber MB, MacConnie SE, Schonfeldt B, Shunk T. A 518
school-based cardiovascular exercise and nutrition program with parent participation: 519
An evaluation study. Children in Health Care 1996;25:221-235. 520
58. Mangunkusumo RT, Brug J, de Koning HJ, van der Lei J, Raat H. School-based 521
Internet-tailored fruit and vegetable education combined with brief counselling 522
increases children's awareness of intake levels. Public Health Nutrition 2007;10:273-523
279. 524
59. Taylor RW, McAuley KA, Barbezat W, Strong A, Williams SM, Mann JI. APPLE 525
Project: 2-y findings of a community-based obesity prevention program in primary 526
school age children. Am J Clin Nutr 2007;86:735-742. 527
60. Foerster SB, Gregson J, Beall D, et al. The California Children's 5 a Day- Power Play! 528
Campaign: Evaluation of a Large-Scale Social Marketing Initiative: Family & 529
Community Health April 1998;21(1):46-64. 530
61. Eriksen K, Haraldsdottir J, Pederson R, et al. Effect of a fruit and vegetable 531
subscription in Danish schools. Public Health Nutrition 2003;6:57-63. 532
62. Lowe CF, Horne PJ, Tapper K, Bowdery M, Egerton C. Effects of a peer modelling 533
and rewards-based intervention to increase fruit and vegetable consumption in 534
children. Eur.J.Clin.Nutr 2004;58:510-522. 535
63. Spiegel SA, Foulk D. Reducing Overweight through a Multidisciplinary School-based 536
Intervention[ast]. Obesity 2006;14:88-96. 537
64. Fogarty A, Antoniak M, Venn A, et al. Does participation in a population-based 538
dietary intervention scheme have a lasting impact on fruit intake in young children? 539
Int.J.Epidemiol. 2007. 540
65. Reynolds KD, Franklin FA, Binkley D, et al. Increasing the fruit and vegetable 541
consumption of fourth-graders: results from the high 5 project. Prev.Med. 542
2000;30:309-319. 543
66. Baranowski T, Davis M, Resnicow K, et al. Gimme 5 fruit, juice, and vegetables for 544
fun and health: outcome evaluation.[erratum appears in Health Educ Behav 2000 545
Jun;27(3):390]. Health Education & Behavior 2000;27:96-111. 546
67. Baranowski T, Baranowski J, Cullen KW, et al. Squire's Quest! Dietary outcome 547
evaluation of a multimedia game. American Journal of Preventive Medicine 548
2003;24:52-61. 549
68. Govula C. Culturally Appropriate Nutrition Lessons Increased Fruit and Vegetable 550
Consumption in American Indian Children. Topics in Clinical Nutrition, 551
69. Bere E, Veierod MB, Klepp KI. The Norwegian School Fruit Programme: evaluating 553
paid vs. no-cost subscriptions. Prev Med 2005;41:463-70. 554
70. Moore L, Tapper K. The impact of school fruit tuck shops and school food policies on 555
children's fruit consumption: a cluster randomised trial of schools in deprived areas. J 556
Epidemiol Community Health 2008;62:926-31. 557
71. Anderson A, Porteous L, Foster E, et al. The impact of a school-based nutrition 558
education intervention on dietary intake and cognitive and attitudinal variables 559
relating to fruits and vegetables. Public Health Nutrition 2005;8:650-656. 560
72. Perry CL, Bishop DB, Taylor G, et al. Changing fruit and vegetable consumption 561
among children: the 5-a-Day Power Plus program in St. Paul, Minnesota. Am.J.Public 562
Health 1998;88:603-609. 563
73. Reinaerts E, de Nooijer J, Candel M, de Vries N. Increasing children's fruit and 564
vegetable consumption: distribution or a multicomponent programme? Public Health 565
Nutr 2007;10:939-47. 566
74. Sahota P, Rudolf MC, Dixey R, Hill AJ, Barth JH, Cade J. Randomised controlled 567
trial of primary school based intervention to reduce risk factors for obesity. BMJ 568
2001;323:1029-1032. 569
75. Reinaerts E, Crutzen R, Candel M, De Vries NK, De Nooijer J. Increasing fruit and 570
vegetable intake among children: comparing long-term effects of a free distribution 571
and a multicomponent program. Health Educ. Res. 2008;23:987-996. 572
76. Te Velde SJ, Brug J, Wind M, et al. Effects of a comprehensive fruit- and vegetable-573
promoting school-based intervention in three European countries: the Pro Children 574
Study. Br J Nutr 2008;99:893-903. 575
77. Wind M, Bjelland M, Perez-Rodrigo C, et al. Appreciation and implementation of a 576
school-based intervention are associated with changes in fruit and vegetable intake in 577
10- to 13-year old schoolchildren--the Pro Children study. Health Educ Res 578
2008;23:997-1007. 579
78. Reinaerts EB, de Nooijer J, de Vries NK. Fruit and vegetable distribution program 580
versus a multicomponent program to increase fruit and vegetable consumption: which 581
should be recommended for implementation? J Sch Health 2007;77:679-86. 582
79. Kremer PJ, Bell AC, Swinburn BA. Calibration and reliability of a school food 583
checklist: a new tool for assessing school food and beverage consumption 3. Asia 584
Pac.J.Clin.Nutr 2006;15:465-473. 585
80. Weichselbaum E, Gibson-Moore H, Ballam R, Buttriss JL, on behalf of the Network 586
of European Nutrition F. Nutrition in schools across Europe: a summary report of a 587
meeting of European Nutrition Foundations, Madrid, April 2010. Nutrition Bulletin 588
2011;36:124-141. 589
81. Robinson-O'Brien R, Story M, Heim S. Impact of Garden-Based Youth Nutrition 590
Intervention Programs: A Review. Journal of the American Dietetic Association 591
2009;109:273-280. 592
82. Birch LL, McPhee L, Shoba BC, Pirok E, Steinberg L. What kind of exposure reduces 593
children's food neophobia? Looking vs. tasting. Appetite 1987;9:171-178. 594
83. Wardle J, Cooke LJ, Gibson EL, Sapochnik M, Sheiham A, Lawson M. Increasing 595
children's acceptance of vegetables; a randomized trial of parent-led exposure. 596
Appetite 2003;40:155-162. 597
84. McAleese JD, Rankin LL. Garden-based nutrition education affects fruit and 598
vegetable consumption in sixth-grade adolescents. J Am Diet Assoc 2007;107:662-5. 599
85. Day M, Strange K, McKay H, Naylor P. Action Schools! BC - Healthy Eating: 600
School Children. Canadian Journal of Public Health Revue Canadienne de Sante 602
Publique 2008;99:328-331. 603
86. Foster GD, Sherman S, Borradaile KE, et al. A policy-based school intervention to 604
prevent overweight and obesity. Pediatrics 2008;121:e794-802. 605
87. Gortmaker SL, Cheung LW, Peterson KE, et al. Impact of a school-based 606
interdisciplinary intervention on diet and physical activity among urban primary 607
school children: eat well and keep moving. Arch.Pediatr.Adolesc.Med. 1999;153:975-608
983. 609
88. Gortmaker SL, Peterson K, Wiecha J, et al. Reducing obesity via a school-based 610
interdisciplinary intervention among youth: Planet Health. Arch.Pediatr.Adolesc.Med. 611
1999;153:409-418. 612
89. Tak NI, te Velde SJ, Brug J. Ethnic differences in 1-year follow-up effect of the 613
Dutch Schoolgruiten Project ? promoting fruit and vegetable consumption among 614
primary-school children. Public Health Nutrition 2007;10:1497-1507. 615
Table 1: Characteristics of studies included in the review of school-based interventions to increase daily fruit and vegetable (veg) intake. Difference in fruit and vegetable portions between groups is adjusted for baseline whenever possible. Banded rows are not included in the meta-analysis.
Study name (author, year published, country) Sample size Sample age Intervention time: elements included in the intervention
Follow-up period from start of intervention
fruit & vegetable intake in portions at follow up
Difference in fruit & vegetable portions Difference in fruit portions Difference in vegetable portions Control Intervention
Nutrition Education Intervention (Anderson, 2005, UK)(71)
129 6-11 years
9 months: Curriculum, communications, food provision & marketing, food preparation/tasting
9 months 163g (2.0) 235g (2.9) 0.9 0.9 0
Gimme 5 (Baranowski, 2000, USA)(66)
3347 Mean of 8 years
9 months: Curriculum, communications, food marketing, goal setting & problem solving, home based projects
9 months
21 months
2.1 (1 year)
2.1 (2 year)
2.3 (1 year)
2.3 (2 year)
0.2
0.2
n/a n/a
Squire’s Quest
(Baranowski, 2003, USA)(67)
1489 8-12 years
5 weeks: 10 session psycho-educational multimedia game
< 3 months n/a n/a 0.9 0.5 0.2
School Fruit Program (Bere, 2005, Norway)(69)
556 11-12 years
9 months: Free school fruit & veg distribution
9 months 1.0 (median) 2.0 (median) 1.0 n/a n/a
Free School Fruit (Bere, 2006, Norway)(55)
517 10-11 years
21 months: Free school fruit & veg distribution
9 months 21 months 1.84 1.57 2.47 2.09 0.6 0.5 n/a n/a n/a n/a
Fruit & Veg Make the Marks (Bere, 2006, Norway)(56)
Study name (author, year published, country)
Sample size
Sample age
Intervention time: elements included in the intervention
Follow-up period from start of intervention
fruit & vegetable intake in portions at follow up
Difference in fruit & vegetable portions
Difference in fruit portions
Difference in vegetable portions Control Intervention
setting, home based projects
Action Schools! (Day, 2008, Canada)(85)
444 10 years 3 months: Curriculum, food tasting, school environment, goal setting
3 months 2.68 2.55 -0.23 0.13 0.1
Fruit & veg subscription (Eriksen, 2003, Denmark)
313 6-10 years
1.5 months: fruit and vegetable subscription
1.5 months 3.1 3.5 0 n/a n/a
5 a Day Power Play! School only (Foerster, 1998, USA)(60)
2684 7-9 years 2 months: Curriculum, school environment
3 months 2.3 2.9 0.6 n/a n/a
5 a Day Power Play! School & community (Foerster, 1998, USA)(60)
7-9 years 2 months: Curriculum, school environment, community
3 months 2.3 3.3 1.0 n/a n/a
The National Schools Fruit Scheme (Fogarty, 2007, UK)(64)
3382 7-8 years 12 months: fruit distribution scheme
24 months 2.0 1.7 0 n/a n/a
School Nutrition Policy initiative (Foster, 2008, USA)(86)
774 Mean of 11 years
21 months: education, policy, social marketing and parent outreach
21 months 4.3 4.2 0.0 n/a n/a
Eat Well & keep moving (Gortmaker, 1999, USA)(87)
336 Mean of 9 years
21 months: Curriculum, school environment, home based projects
Study name (author, year published, country) Sample size Sample age Intervention time: elements included in the intervention
Follow-up period from start of intervention
fruit & vegetable intake in portions at follow up
Difference in fruit & vegetable portions Difference in fruit portions Difference in vegetable portions Control Intervention
Planet Health (Gortmaker, 1999, USA)(88) 593 boys 564 girls Mean of 11.7 years
21 months: Curriculum, home based projects
21 months 3.6
3.9
3.6
3.6
0.2
0.3
n/a n/a
American Indian Nutrition (Govula, 2007, USA)(68)
33 8-11 years
2 months: Curriculum 3 months 4.7 4.9 0.2 -0.5 0.7
Cardiovascular Exercise and Nutrition Program (Hopper, 1996, USA)(57)
97 7-9 years 3 months: Curriculum, home based projects
3 months 3.9 4.4 0.4 n/a n/a
Food Dudes (Lowe, 2004, UK)(62)
36 4 to 7 years
1 month: social marketing using videos as part of curriculum
1 month n/a n/a 1.9 n/a n/a
8 to 11 years
n/a n/a 1.6 n/a n/a
Internet tailored advice (Mangunkusumo, 2006, The Netherlands)(58)
486 Mean of 10.3 years
3 months: Internet based feedback from questionnaire
3 months 2.14 2.06 0 0 0
School Fruit Tuck Shops(Moore, 2008, UK)(70)
1612 10-11 years
9 months: school environment (tuck shops selling fruit)
12 months 2.5 2.5 n/a 0.1 n/a
5 a day Power plus (Perry, 1998, USA)(72)
407 9-10 years
9 months: Curriculum, school environment, food provision/
Study name (author, year published, country) Sample size Sample age Intervention time: elements included in the intervention
Follow-up period from start of intervention
fruit & vegetable intake in portions at follow up
Difference in fruit & vegetable portions Difference in fruit portions Difference in vegetable portions Control Intervention
marketing, home based projects, industry involvement
School Fruit & Vegetable Scheme: remaining on scheme at 7 months (Ransley, 2007, UK)(52)
3405 5 years 6 months: Free school fruit & veg distribution
3 months 7 months 3.3 3.2 n/a n/a 0.7 0.2 0.6 0.3 0 -0.2
School Fruit & Vegetable Scheme: leaving scheme by 7 months (Ransley, 2007, UK)(52)
6 years 6 months: Free school fruit & veg distribution
3 months 7 months n/a n/a 0.5 -0.2 0.5 0 0 -0.3
Fruit & veg distribution program (Reinaerts, 2008, The Netherlands)(75)
436 Mean of 8 years
9 months: Free school fruit & veg distribution
9 months 21 months 1.7 1.66 2.0 1.87 0.3 0.1 0.3 0.1 0 0 Multicomponent program (Reinaerts, 2008, The Netherlands)(75)
351 Mean of 8 years
9 months: Curriculum, food provision, communications, home based projects, community 9 months 21 months 1.65 1.66 1.82 1.79 0.2 0.1 0.2 0.1 0 0
High 5 (Reynolds, 2000, USA)(65)
1426 Mean of 8.7 years
21 months: Curriculum, food tasting, problem solving, food service, home based projects
1year
2 years
2.28 (1 year)
2.21 (2 year)
3.96 (1 year)
3.20 (2 year) 1.7
1.0
Study name (author, year published, country)
Sample size
Sample age
Intervention time: elements included in the intervention
Follow-up period from start of intervention
fruit & vegetable intake in portions at follow up
Difference in fruit & vegetable portions
Difference in fruit portions
Difference in vegetable portions Control Intervention
UK)(74) 8.4 years school environment, food service
WAY program (Spiegel, 2006, USA)(63)
1007 9-11 years
9 months: Curriculum, problem solving, home based projects
9 months 0.55 0.1 0.45
Schoolgruiten project (Tak, 2007, Netherlands)(89)
450 (white)
236 (ethnic )
9-12 years
9 months: Free school fruit & veg distribution
12 months 2.54
3.07
2.83
3.3
n/a
n/a
n/a
n/a
0.1
0
APPLE (Taylor, 2007, New Zealand) (59)
288 5-12 years
9 months: Curriculum, free fruit and veg, home based projects
Table 2: Pooled effects of studies which excluded and included fruit juice on daily portions of fruit and vegetable consumption by subgroup analysis stratified by
randomization method, study design, length of follow up, type of dietary assessment and
children’s age.
Variables No. of
studies
Pooled estimate for sub-group (95% CI)
I2
(%)
P value for heterogeneity within sub-group
P value for heterogeneity between sub-groups
Studies excluding fruit juice
Randomization
Randomized 4 0.26 (0.12, 0.40) 1 0.39
Not randomized 4 0.26 (-0.17, 0.69) 69 0.02 0.83
Unclear 3 0.35 (-0.28, 0.98) 68 0.04
Study design
Multi-component 8 0.29 (0.08, 0.49) 40 0.11 0.47
Single component 3 0.15 (-0.26, 0.56) 67 0.05 Length of follow up
2 school years 6 0.26 (0.05, 0.47) 49 0.08
1 school year 3 0.08 (-0.29, 0.46) 48 0.15 0.90
Less than 1 school year 2 0.72 (0.14, 1.30) 0 0.53 Type of dietary assessment
24hr recall 5 0.46 (0.07, 0.86) 54 0.07
Un-weighed diary 3 0.08 (-0.29, 0.46) 48 0.15 0.31
FFQ 3 0.24(0.08, 0.40) 11 0.32
Mean age of children 16 0.02 (-0.07, 0.11) 0.68
Studies Including fruit juice
Randomization
Randomized 5 0.24(0.12, 0.35) 0 0.51
Not randomized 5 0.33(-0.13, 0.08) 67 0.01 0.40
Unclear 4 0.54(-0.04, 1.12) 78 <0.01
Study design
Multi-component 10 0.36(0.16, 0.56) 62 0.01 0.48
Single component 4 0.22(-0.25, 0.7) 68 0.03 Length of follow up
2 school years 8 0.33(0.12, 0.54) 68 0.33
1 school year 3 0.08 (-0.29, 0.46) 48 0.15 0.88
Less than 1 school year 3 0.82(0.20. 1.45) 10 0.33 Type of dietary assessment
24hr recall 6 0.58(0.20, 0.96) 64 0.02
Un-weighed diary 4 0.12(-0.11, 0.35) 39 0.18 0.14
FFQ 4 0.22(-0.02, 0.46) 42 0.16
Figure 2: Pooled estimate of difference in daily intake of portions of fruit and
vegetables (veg) between intervention and control groups; using longest follow up data available and excluding studies that combined fruit and fruit juice. Weight was
Figure 3: Pooled estimate of difference in daily portions of fruit and vegetables (veg) consumed between intervention and control group; using longest follow up data available and including studies that combined fruit and fruit juice. Weight was
Figure 5: Pooled estimate of difference in daily portions of vegetables (veg) consumed between intervention and control group; using longest follow up data available and including studies that combined fruit and fruit juice. Weight was